U.S. patent application number 13/836349 was filed with the patent office on 2013-10-24 for winding core for coil winding device.
This patent application is currently assigned to KABUSHIKI KAISHA TOYOTA JIDOSHOKKI. The applicant listed for this patent is KABUSHIKI KAISHA TOYOTA JIDOSHOKKI. Invention is credited to Kazuyuki YAMAGUCHI.
Application Number | 20130277493 13/836349 |
Document ID | / |
Family ID | 48128086 |
Filed Date | 2013-10-24 |
United States Patent
Application |
20130277493 |
Kind Code |
A1 |
YAMAGUCHI; Kazuyuki |
October 24, 2013 |
WINDING CORE FOR COIL WINDING DEVICE
Abstract
A winding core for a coil winding device having a column shape
with corners each having a rounded cross-section is used for
forming a coil by winding a wire around the winding core into the
coil of a polygonal shape. The winding core includes a helical
continuous surface extending spirally around an axis of the winding
core.
Inventors: |
YAMAGUCHI; Kazuyuki;
(Aichi-ken, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KABUSHIKI KAISHA TOYOTA JIDOSHOKKI |
Kariya-shi |
|
JP |
|
|
Assignee: |
KABUSHIKI KAISHA TOYOTA
JIDOSHOKKI
Kariya-shi
JP
|
Family ID: |
48128086 |
Appl. No.: |
13/836349 |
Filed: |
March 15, 2013 |
Current U.S.
Class: |
242/604 |
Current CPC
Class: |
H01F 41/071 20160101;
B65H 75/18 20130101; H01F 41/098 20160101; B65H 75/242
20130101 |
Class at
Publication: |
242/604 |
International
Class: |
B65H 75/18 20060101
B65H075/18 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 19, 2012 |
JP |
2012-095967 |
Claims
1. A winding core for a coil winding device, the winding core
having a column shape with corners each having a rounded
cross-section, the winding core used for forming a coil by winding
a wire around the winding core into the coil of a polygonal shape,
the winding core comprising: the corners each having a helical
continuous surface extending spirally around an axis of the winding
core.
2. The winding core according to claim 1, wherein the winding core
is divided into a plurality of core bars, and contacting surfaces
of the core bars with the wires at the corners of the winding core
are moved inward and separated away from the wire after the winding
of the wire is completed.
3. The winding core according to claim 2, wherein the winding core
includes two core bars.
4. The winding core according to claim 2, wherein the winding core
includes four core bars.
5. The winding core according to claim 2, wherein each of spaces
formed between the core bars extends in a helical manner.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a winding core for a coil
winding device.
[0002] When a wire is bent into a generally square shape or any
other polygonal shape in winding the wire around a winding core of
a winder to form a coil, the wire is sprung back from the intended
bending angle. In the coil winding device disclosed in Japanese
Patent Application Publication No. 2010.4589, the winding core of
the winder is formed helically with the springback taken into
previous consideration. More specifically, the winding core
includes four core bars each having a substantially rectangular
cross-section with four rounded corners and the wire is wound
around the winding core for N times (N is an integer of two or
more) to form a coil. The winding core has winding tracks forming N
steps for winding wire and the winding tracks are formed such that
each four corners of the winding tracks are circumferentially
deviated every step to make the winding core in.sub.to a helical
shape.
[0003] Referring to FIG. 9A showing the background art according to
the above-cited Publication No. 2010-4589, the helical winding core
100 has winding tracks 101, 102, 103, 104 and a step is formed
between any two adjacent winding tracks, as shown in FIG. 9A. Each
of the winding tracks 101, 102, 103, 104 has a contacting surface
with which the wire (flat wire) 110 is in perpendicular contact.
The wire 110 is pressed against the winding core 100 by the guide
member 120 of a pressing roller. The wire 110 pressed against the
step by the guide member 120 is moved to the adjacent step formed
between the winding tracks 101, 102, 103, 104, so that the wire 110
is damaged by the step. For preventing the above damage to the wire
110, the winding tracks 101, 102, 103, 104 may be widened or the
width W of the winding tracks 101, 102, 103, 104 may be increased,
as shown in FIG. 9B so that the wire 110 is not moved to the
adjacent step. However, widening the tracks 101, 102, 103, 104
widens the clearance between any two adjacent turns of the wire in
the axial direction of the winding core 100 and increases the total
length of the coil.
[0004] The present invention is directed to providing a winding
core for a .sub.coil winding device by which damage to a wire
hardly occurs and an increase of the total length of wound coil is
prevented.
SUMMARY OF THE INVENTION
[0005] In accordance with the present invention, a winding core for
a coil winding device having a column shape with corners each
having a rounded cross-section is used for forming a coil by
winding a wire around the winding core into the coil of a polygonal
shape. The winding core includes a helical continuous surface
extending spirally around an axis of the winding core.
[0006] Other aspects and advantages of the invention will become
apparent from the following description, taken in conjunction with
the accompanying drawings, illustrating by way of example the
principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The invention together with objects and advantages thereof,
may best be understood by reference to the following description of
the presently preferred embodiments together with the accompanying
drawings in which:
[0008] FIG. 1 is a schematic perspective view of a coil winding
device having a winding core according to a first preferred
embodiment of the present invention;
[0009] FIG. 2 is a perspective view of the winding core of FIG.
1;
[0010] FIG. 3 is an end view of the winding core of FIG. 1;
[0011] FIG. 4 is a longitudinal sectional schematic view of the
winding core of FIG. 1, showing the expanded state of the winding
core;
[0012] FIG. 5 is a longitudinal sectional schematic view of the
winding core of FIG. 1, showing the contracted state of the winding
core;
[0013] FIG. 6 is an end view of a coil winding device having a
winding core according to another embodiment of the present
invention;
[0014] FIG. 7 is an end view of a coil winding device having a
winding core according to yet another embodiment of the present
invention;
[0015] FIG. 8 is a schematic front view of a winding core according
to still yet another embodiment of the present invention;
[0016] FIG. 9A is a schematic front view showing a winding core of
the coil winding device according to the background art of the
present invention, and
[0017] FIG. 9B is a schematic front view showing a modified over
the winding core of FIG. 9A.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] The following will describe a coil winding device according
to a first preferred embodiment with reference to FIGS. 1 through
5. It is noted that the arrows X, Y and Z in the drawing show three
different directions in the three-dimensional coordinate system of
the coil winding device.
[0019] Referring to FIG. 1, reference numeral 1 designates a coil
winding device. The coil winding device 1 includes a winder 10
having a winding core 20. The coil winding device 1 is used for
forming a coil by winding a flat wire 50 around the columnar
winding core 20 into a coil of a generally rectangular shape. The
flat wire 50 has a rectangular cross-section and is wound edgeways
to form the coil. The winding core 20 is rotatably supported.
[0020] Referring also to FIGS. 2, 3, the winding core 20 is divided
into four core bars, namely a first core bar 21, a second core bar
22, a third core bar 23 and a fourth core bar 24.
[0021] The winding core 20 as a whole has a generally square column
shape with four corners, namely first through fourth corners C1,
C2, C3, C4 each of which is rounded. The first through fourth
corners C1, C2, C3, C4 have a rounded cross-section. The first core
bar 21 has the first corner C1. The second core bar 22 has the
second corner C2. The third core bar 23 has the third corner C3.
The fourth core bar 21 has the fourth corner C4. L1 in FIGS. 2 and
3 indicates the axis of the square columnar winding core 20.
[0022] The first through fourth core bars 21, 22, 23, 24 have a
shape of a twisted rod and the first through fourth corners C1, C2,
C3, C4 thereof have a helical continuous smooth surface extending
spirally around the axis L1.
[0023] A first helical space G1 is formed between the first and the
second core bars 21, 22, as shown in FIGS. 1 and 3. Similarly, a
second helical space G2 is formed between the second and the fourth
core bar 22, 24, a third helical space G3 is formed between the
first and the third core bar 21, 23 and a fourth helical space G4
is formed between the third and the fourth core bars 23, 24, as
shown in FIGS. 1 and 3.
[0024] As shown in FIG. 3, the first through fourth core bars 21,
22, 23, 24 are slidably supported by means of a slide mechanism
such that the first through fourth core bars 21, 22, 23, 24 can be
moved toward and away from the center O of the winding core 20. The
arrows .alpha. in FIGS. 2 and 3 show the directions in which the
respective first through fourth core bars 21, 22, 23,24 are moved
toward the center O. After the winding of the flat wire 50 is
completed, the first through fourth core bars 21, 22, 23, 24 slide
inward or in the direction .alpha., so that the contacting surfaces
of the first through fourth core bars 21, 22, 23, 24 with the flat
wire 50 at the rounded first through fourth corners C1, C2, C3, C4
are moved inward and separated away from the flat wire 50.
[0025] The coil winding device 1 further includes a lower plate
(bottom block) 30 and an upper plate (top block) 31. As shown in
FIG. 1, the first through fourth core bars 21, 22, 23, 24 are
disposed upright on the lower plate 30. The upper plate 31 is
provided on the top of the first through fourth core bars 21, 22,
23, 24. In other words, the first through fourth core bars 21, 22,
23, 24 are supported and held between the lower plate 30 and the
upper plate 31 in an upright position.
[0026] Referring to FIG. 4, an arm 32 is disposed above the upper
plate 31 and extends horizontally. The arm 32 is fastened at the
proximal end thereof to the upper plate 31 by bolts 33, 34. A
center shaft 35 extends through the center part of the lower plate
30. The center shaft 35 is supported at the lower part thereof by a
bearing 36 so as to be movable up and down. The center shaft 35
extends also through the center of the upper plate 31 and is
supported at the upper part thereof by a bearing 37 so as to be
movable up and down.
[0027] The lower plate 30 has on the top surface thereof a
plurality of guide members 38. Similarly, the upper plate 31 has on
the bottom surface thereof a plurality of guide members 39. The
first through fourth core bars 21, 22, 23, 24 are slidable in
radial direction toward and away from the center O of the winding
core 20 while being guided by the guide members 38, 39.
[0028] The lower plate 30 has a stop projection 40 on the top
surface thereof and the upper plate 31 has a stop projection 41 on
the bottom surface thereof. The center shaft 35 extends through the
center of the winding core 20.
[0029] The center shaft 35 has three large-diameter portions 35A,
35C, 35E and two small-diameter portions 35B, 35D. The
large-diameter portion 35A, the small-diameter portion 35B, the
large-diameter portion 35C, the small-diameter portion 35D and the
large-diameter portion 35E are positioned in this order from the
bottom to the top of the center shaft 35.
[0030] The first through fourth core bars 21, 22, 23, 24 (winding
core 20) have on the inner peripheral surfaces thereof
large-diameter portions 25, 27, 29 and small-diameter portions 26,
28. The large-diameter portion 25, the small-diameter portion 26,
the large-diameter portion 27, the small-diameter portion 28 and
the large-diameter portion 29 are positioned in this order as seen
from the bottom to the top of the winding core 20. As shown in FIG.
5, the winding core 20 is pushed inward by an external actuator
(not shown) such that the inner peripheral surfaces of the first
through fourth core bars 21, 22, 23, 24 are brought into contact
with the outer peripheral surface of the center shaft 35. Thus, the
first through fourth core bars 21, 22, 23, 24 are moved inward or
toward the center O, so that the diameter of the winding core 20 is
reduced.
[0031] The center shaft 35 is movable up and down. When the
small-diameter portions 26, 28 of the first through fourth core
bars 21, 22, 23, 24 and the small-diameter portions 35B, 35D of the
center shaft 35 are in contact with each other, the first through
fourth core bars 21, 22, 23, 24 are located in the contracted
position, as shown in FIG. 5. When the small-diameter portions 26,
28 of the first through fourth core bars 21, 22, 23, 24 and the
large-diameter portions 35A, 35C of the center shaft 35 are in
contact with each other, the first through fourth core bars 21, 22,
23, 24 are located in the expanded position, as shown in FIG. 4. At
this time, the first through fourth core bars 21, 22, 23, 24 are
placed in contact with the stop projections 40, 41 formed on the
lower and the upper plates 30, 31, respectively.
[0032] When the center shaft 35 is moved upward, the first through
fourth core bars 21, 22, 23, 24 of the winding core 20 are
separated by being pushed away from each other in radial direction
by steps of the center shaft 35. Thus, the coil winding device 1 is
placed in the expanded position shown in FIG. 4. When the center
shaft 35 is moved downward, on the other hand, the large-diameter
portions 35A, 35C, 35E of the center shaft 35 are located in the
large-diameter portions 25, 27, 29 of the first through fourth core
bars 21, 22, 23, 24 with clearances formed between the
large-diameter portions 35A, 35C, 35E and the large-diameter
portions 25, 27, 29, respectively. Then, the clearances are reduced
by the external actuator. Thus, the coil winding device 1 is placed
in the contracted position as shown in FIG. 5.
[0033] Winding of the wire is performed around the winding core 20
in the expanded position shown in FIG. 4 and, after completion of
the winding of wire, the wound wire (coil) is removed from the
winding core 20 which is contracted as shown in FIG. 5. The flat
wire 50 is wound while being guided along the winding core 20 by a
guide member (not shown). In the winding, the flat wire 50 is
pressed at the short side of the rectangular cross-section of the
flat wire 50 against the winding surface (or contact surface) of
the winding core 20. In the winding of the flat wire 50, the
relative positions of the flat wire 50 and the winding core 20 in
the vertical direction is changed. Specifically, the winding of the
flat wire 50 is performed while the winding core 20 is being moved
downward with the flat wire 50 kept at a predetermined height.
[0034] The following will describe the operation of the coil
winding device 1 (winding core 20) constructed as described above.
With the center shaft 35 placed in the raised position as shown in
FIG. 4, the small-diameter portions 26, 28 of the first through
fourth core bars 21, 22, 23, 24 and the large-diameter portions
35A, 35C of the center shaft 35 are in contact with each other, so
that the first through the fourth core bars 21, 22, 23, 24 are
located away from each other.
[0035] In this state of the winding core 20, one end of the flat
wire 50 is fixed to the winding core 20 of the winder 10. The flat
wire 50 is pressed against the peripheral surface of the winding
core 20 and wound edgeways around the winding core 20 by rotating
the winding core 20, thereby forming a coil.
[0036] As shown in FIGS. 1 and 2, the first through fourth corners
C1, C2, C3, C4 corresponding to the outer peripheral surfaces (side
surfaces) of the winding core 20 around which the flat wire 50 is
wound are formed helically around the axis L1.
[0037] The winding core 20 has a helical shape which is formed with
the springback of the wound flat wire 50 taken into consideration
preciously, so that the flat wire 50 removed from the winding core
20 and sprung back takes an intended shape having no
distortion.
[0038] After the winding of the flat wire 50 is completed, the
center shaft 35 is moved downward and the small-diameter portions
26, 28 of the first through fourth core bars 21, 22, 23, 24 and the
small-diameter portions 35B, 35D are in contact with each other, so
that the first through the fourth core bars 21, 22, 23, 24 are
moved to the contracted position of FIG. 5. That is, after winding
of the flat wire 50, the first through the fourth core bars 21, 22,
23, 24 are moved inwardly or toward the axis L1, so that the wound
flat wire 50 may be removed from the winding core 20.
[0039] The winding angle of the winding core 20 is corrected by
twisting the winding core 20 around the rotation center (center
axis) of the winding core 20 by an amount of the springback of the
winding core 20. The first through fourth corners C1, C2, C3, C4
have a helical continuous smooth surface extending spirally around
the axis L1, so that the wire is hardly susceptible to a damage by
the steps as described with reference to FIG. 9A and an increase of
the total length of the completed coil shown in FIG. 9B is
prevented. Since the first through fourth corners C1, C2, C3, C4 of
the winding core 20 have a helical continuous smooth surface such
that the completed coil formed by bending slips thereon in the
axial direction thereof, damage to the coil by the steps hardly
occurs and an increase of the total length of the completed coil
and twisting caused by springback are prevented.
[0040] The formed coil caught on the winding core 20 due to
springback is pulled out easily from the winding core 20 by
contracting the winding core 20. After pulling out the coil from
the winding core 20, the winding core 20 is expanded so as to move
the first through fourth core bars 21, 22, 23, 24 back in the
expanded position.
[0041] The following advantageous effects are obtained in the
embodiment.
(1) In the coil winding device 1, the winding core 20 has a column
shape having the rounded first through fourth corners C1, C2, C3,
C4 each having a rounded cross-section. The first through fourth
corners C1, C2, C3, C4 have a helical continuous smooth surface
extending spirally around the axis L1 of the winding core 20. Thus,
the wire (flat wire 50) is prevented from damage by the steps as
described earlier with reference to FIGS. 9A and 9B. Since damage
of the wire by the steps need not to be considered, the clearance
between any two adjacent turns of wire in the axial direction of
the winding core 20 is reduced and an increase of the total length
of the wound coil is prevented. Therefore, damage to the wire is
hardly occurred and an increase of the total length of the wound
coil is prevented. (2) The winding core 20 which is divided into a
plurality of the first through fourth core bars 21, 22, 23, 24
movable inwardly away from the wound flat wire 50 allows the wound
wire (coil) to be removed easily from the winding core 20. (3) The
winding core 20 according to the embodiment which is divided into
four core bars 21, 22, 23, 24 having the rounded first through
fourth corners C1, C2, C3, C4 facilitate removal of wound wire
(coil) from the winding core 20 by replacement of the rounded first
through fourth corners C1, C2, C3, C4. (4) The first through fourth
helical spaces G1, G2, G3, G4 formed between the first through
fourth core bars 21, 22, 23, 24 extend in a helical manner. Thus,
the first through fourth corners C1, C2, C3, C4 are formed in a
helical shape, so that the coil is easily pulled out from the
winding core 20.
[0042] The above embodiment may be modified in various ways as
exemplified below.
[0043] In the structure for contracting the winding core 20, the
path of movement of the first through fourth core bars 21, 22, 23,
24 is not limited to the movement in radial direction from the
center of the winding core 20. The first through fourth core bars
21, 22, 23,24 may be moved in any way other than radially as long
as they are moved inwardly. For example, the first through fourth
core bars 61, 62, 63, 64 may be movable in the directions that are
indicated by the double-headed arrows .beta. in FIG. 6.
Specifically, the double-headed arrows .beta. in FIG. 6 is directed
obliquely with respect to an imaginary line extending radially
through the center O of the winding core 20.
[0044] In other words, the winding core 20 may be configured so
that the first through fourth core bars 61, 62, 63, 64 are movable
inwardly so as to allow the coil to be disengaged from the winding
core 20 and to be removed therefrom.
[0045] The provision of the helically extending first through
fourth helical spaces G1, G2, G3, G4 allows the first through
fourth core bars 61, 62, 63, 64 to be moved in the .beta.
directions other than the direction toward away from the center O
(or radial direction).
[0046] According to the above embodiment, the winding core 20 is
divided into four core bars. Furthermore, the winding core includes
more than two core bars. FIG. 7 shows an embodiment wherein the
winding core 20 includes two first and second core bars 71, 72.
[0047] The structure for expanding and contracting the winding core
20 is not limited to the slide mechanism, but may be link mechanism
or cam mechanism. Any structure that allows a coil to be removed
from the winding core 20 is acceptable. FIG. 8 shows an example of
the link mechanism, wherein first and second core bars 80, 81 are
pivotally supported at a position adjacent to the bottom thereof by
a pin 90 and the first and the second core bars 80, 81 are pivoted
as indicated by arrows by a cylinder 95 that is operative connected
to the bottom of the first and the second core bars 80, 81 through
a pin 91.
[0048] The wire to be wound is not limited to a flat wire, but may
be any other wire, such as a wire having a circular cross-section.
The winding core 20 or the coil is not limited to have a
rectangular shape, but may have any other shape, such as a rhombus
shape or any other polygonal shape.
[0049] The winding core need not be formed by a plurality of core
bars, but may be formed by a single core bar.
* * * * *